Exodus 34:22

22 aYou shall observe the Feast of Weeks, the firstfruits of wheat harvest, and the Feast of Ingathering at the year’s end.

Numbers 28:26

Offerings for the Feast of Weeks

26“On bthe day of the firstfruits, when you offer a grain offering of new grain to the Lord at your Feast of Weeks, you shall have a holy convocation. You shall not do any ordinary work,

Deuteronomy 16:10

10Then you shall keep cthe Feast of Weeks to the Lord your God with dthe tribute of a freewill offering from your hand, which you shall give eas the Lord your God blesses you.
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